Explanation:
1 , 14x=-6+21
14x=15 , divide both sides by q4 to get the value of x
x=15/14
2 , x1=x
-x=9-12
-x=-3 , divide both side by -1
x=3
3, 13x=6_61
13x= 55 , divide both sides by 13
x=55/13
4, 1-2x+81=1+81_2x
82_2x=0
-2x=-82 , divide both sides by -2
x=41
So, all of them have a solution